It seems these tracing messages are outputted by the kde-open5 utility.
I do not think we should hide at xdg-utils level any messages from
underlying tools. However, you may redirect unneeded output on your own.
$ xdg-open readme.pdf >/dev/null
** Changed in: xdg-utils (Ubuntu)
Status: Ne
1.
$ lsb_release -rd
Description:Ubuntu 10.04.3 LTS
Release:10.04
2.
$ apt-cache policy xdg-utils
xdg-utils:
Installed: 1.0.2-6.1ubuntu3.1
Candidate: 1.0.2-6.1ubuntu3.1
Version table:
*** 1.0.2-6.1ubuntu3.1 0
500 http://us.archive.ubuntu.com/ubuntu/ lucid-updates/mai